{"id":"CVE-2026-98385","revision":"627cf29978ad46deaaf7fc51306246f9","records":[{"revision":"627cf29978ad46deaaf7fc51306246f9","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-98385","aliases":[],"title":"sched/cache: Decouple sched_cache_group from mm to fix UAF","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nsched/cache: Decouple sched_cache_group from mm to fix UAF\n\nCurrently the sched cache grouping is by mm and the scheduling statistics\nsched_cache_stat lives in the mm structure.  This ties the life cycle\nof scheduling stats with mm.\n\nIn account_mm_sched(), the scheduling stats are accessed by\ntask->mm->sc_stat.  However, a task may be switching mm on one CPU when\nanother CPU is running account_mm_sched(), and possibly accessing the\nold mm that was freed.  This problem was found when running tests with\nKASAN by Hyunwoo:\n\n  https://lore.kernel.org/lkml/apPb-Dr4nPYuHQOK@v4bel/\n\nInstead of serializing the mm access by introducing extra acquisition of\nrq lock in the mm free path, extract sched_cache_stat from mm_struct,\nrename it as sched_cache_group and manage its life cycle apart from\nmm_struct with its own ref counting.  This allows us in the next patch\naccess sched_cache_group directly from task, and add a refcount\non sched_cache_group when a task links to it. This prevents the use\nafter free issue when accessing stale and released old mm and its\nsched cache stat a task switches to a new mm while account_mm_sched()\nis done elsewhere.\n\nThe other benefit of this restructure is in the future, the grouping of\ntasks to a LLC would have the flexibility to be associated with a user\ndefined grouping, or cgroup, cookie group, numa_group or others instead\nof just with a single mm address space.\n\nRename sched_cache_stat to sched_cache_group and turn it into a refcounted\nobject allocated from mm_struct.  The mm_struct now holds a pointer\n(sched_cache_grp) to this object instead of embedding it.","state":0,"publishedAt":"2026-10-12T05:48:52.248+00:00","modifiedAt":"2026-10-19T09:18:36.187+00:00","affected":[{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"product\": \"Linux\",\n                    \"vendor\": \"Linux\",\n                    \"defaultStatus\": \"unaffected\",\n                    \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n                    \"programFiles\": [\n                        \"include/linux/mm_types.h\",\n                        \"include/linux/sched.h\",\n                        \"kernel/exit.c\",\n                        \"kernel/sched/fair.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"df0d98475954d655571979aa061ecb07d7e00392\",\n                            \"lessThan\": \"852ecb6bc0bc0106f44f74ba3944524732486025\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"df0d98475954d655571979aa061ecb07d7e00392\",\n                            \"lessThan\": \"28f9c0e0a0b94c5d3e1b634db545f6e1f94858c5\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        }\n                    ]\n                }"},{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"product\": \"Linux\",\n                    \"vendor\": \"Linux\",\n                    \"defaultStatus\": \"affected\",\n                    \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n                    \"programFiles\": [\n                        \"include/linux/mm_types.h\",\n                        \"include/linux/sched.h\",\n                        \"kernel/exit.c\",\n                        \"kernel/sched/fair.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"7.2\",\n                            \"status\": \"affected\"\n                        },\n                        {\n                            \"version\": \"0\",\n                            \"lessThan\": \"7.2\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.2.9\",\n                            \"lessThanOrEqual\": \"7.2.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.3\",\n                            \"lessThanOrEqual\": \"*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"original_commit_for_fix\"\n                        }\n                    ]\n                }"}],"metrics":[],"references":["https://git.kernel.org/stable/c/852ecb6bc0bc0106f44f74ba3944524732486025","https://git.kernel.org/stable/c/28f9c0e0a0b94c5d3e1b634db545f6e1f94858c5"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-98385","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-98385","identifiers":["CVE-2026-98385"]},"retained":false,"historicalAffected":[]}],"coverage":[]}